Improvement of the SRH bulk lifetime upon formation of n-type POLO junctions for 25% efficient Si solar cells

authored by

Jan Krügener, Felix Haase, Michael Rienäcker, Rolf Brendel, H. Jörg Osten, Robby Peibst

Abstract

Carrier-selective contact schemes, like polysilicon on oxide (POLO), provide low contact resistivities while preserving an excellent passivation quality. These junctions offer an important additional feature compared to a-Si/c-Si heterojunctions. We find that the formation of n-type POLO junctions lead to a huge increase of the Shockley-Read-Hall (SRH) lifetime of the substrate, a prerequisite for highly efficient solar cells. The SRH lifetime improvement can be observed for both bulk polarities and for a variety of bulk resistivities. Thus we suggest that the highly doped POLO junction getters impurities that have more or less symmetric SRH capture cross sections. We are able to achieve SRH lifetimes of > 50 ms. By applying POLO junctions to interdigitated back contact cells, we achieve cells with an efficiency of 25%.

Organisation(s)

Institute of Electronic Materials and Devices
Laboratory of Nano and Quantum Engineering

External Organisation(s)

Institute for Solar Energy Research (ISFH)

Type

Article

Journal

Solar Energy Materials and Solar Cells

Volume

173

Pages

85-91

No. of pages

7

ISSN

0927-0248

Publication date

12.2017

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials, Renewable Energy, Sustainability and the Environment, Surfaces, Coatings and Films

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1016/j.solmat.2017.05.055 (Access: Closed)